Design optimisation procedure for fibre metal laminates based on fatigue crack initiation

A design optimisation procedure for fibre metal laminates based on fatigue crack initiation is presented. The state-of-the-art design method is a solution-oriented analysis, where only selected lay-ups are assessed for satisfying the design criteria. This study aims to develop a reversed design procedure where the lay-ups are obtained as design solutions. Therefore, a genetic algorithm procedure is developed to find the optimal lay-up satisfying the required fatigue life. The accuracy of the prediction method for crack initiation depends on the selected S-N curve of the constituent metal, which is observed to influence the obtained design solutions. Additionally, it was observed that the settings of genetic algorithm need to be tuned to obtain a robust optimisation methodology. In conclusion, with the presented methodology appropriate design solutions were obtained that satisfy the minimum fatigue life.